What problem does it solve? Setting up reinforcement learning post-training for large language models requires coordinating distributed training (Megatron-LM) with high-throughput inference (SGLang), managing data buffers, and debugging weight synchronization—tasks that are error-prone without structured guidance. ## Core Features & Use Cases - GRPO and Async Training Workflows: Step-by-step launch commands for standard GRPO, asynchronous training, and multi-turn agentic training with tool calling. - Configuration Reference: Complete argument taxonomy covering Megatron, SGLang, and slime-specific parameters with the batch-size constraint formula. - Troubleshooting Playbook: Solutions for SGLang crashes, weight sync timeouts, OOM errors, reward collapse, and checkpoint loading failures. - Use Case: Train a Qwen3-4B reasoning model with GRPO by sourcing a pre-configured model script, preparing JSONL prompt data, and launching train.py with validated parameters. ## Quick Start Ask the assistant to help you launch a GRPO training run for a Qwen3 model using slime with your JSONL prompt dataset.